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BackgroundMultidrug-resistant strains of the genus Aeromonas can produce various β-lactamases that confer resistance to a broad spectrum of β-lactams, which poses a significant public health threat due to their emergence and spread in clinical settings and natural environments. Therefore, a comprehensive investigation into the antibiotic resistance mechanisms of Aeromonas is scientifically significant.MethodsBetween 2018 and 2021, 78 clinical Aeromonas isolates were collected from human clinical specimens. The MicroScan WalkAway system and average nucleotide identity (ANI) analyses were used to classify the bacterial species. Antibiotic susceptibility was determined through the minimum inhibitory concentration (MIC) test via the agar dilution method. To determine the resistance mechanism and the structure of the resistance gene-related sequences, molecular cloning, whole-genome sequencing and bioinformatic analysis were performed.ResultsAmong the 78 Aeromonas isolates studied in this work, obtained from various specimens from different clinical departments, 77 were classified into seven known species by ANI analysis. Most of the isolates were A. caviae (34.6%, 27/78), followed by A. hydrophila (25.6%, 20/78). Multilocus sequence typing (MLST) revealed that they belonged to 72 sequence types (STs), including 52 new STs. A total of 334 resistance genes of 30 antibiotic resistance genotypes were identified from the genomes, more than half (55.99%, 187/334) of which were β-lactamase genes. The isolates showed much higher rates of resistance to penicillins (penicillin G, 98.7%) and first-generation cephalosporins (cefazolin, 96.2%), but lower resistance rates to fourth-generation cephalosporins (cefepime, 6.4%), monobactams (aztreonam, 5.1%), and carbapenems (imipenem, 1.3% and meropenem, 5.1%). Structural analyses of some β-lactamase genes (such as blaNDM-1 and blaPER-3) related sequences revealed that they were generally associated with mobile genetic elements.ConclusionThe investigation of the correlation between the distribution of β-lactamase genes and Aeromonas resistance phenotypes in this study suggested an urgent need for rigorous monitoring and control to counteract the escalating public health threat posed by the increase in Aeromonas strains harboring extended-spectrum β-lactamase and metallo-β-lactamase genes.

Abstract Cophylogeny has been identified between gut bacteria and their animal host and is highly relevant to host health, but little research has extended to gut bacteriophages. Here we use bee model to investigate host specificity and cophylogeny in the “animal-gut bacteria-phage” tripartite system. Through metagenomic sequencing upon different bee species, the gut phageome revealed a more variable composition than the gut bacteriome. Nevertheless, the bacteriome and the phageome showed a significant association of their dissimilarity matrices, indicating a reciprocal interaction between the two kinds of communities. Most of the gut phages were host generalist at the viral cluster level but host specialist at the viral OTU level. While the dominant gut bacteria Gilliamella and Snodgrassella exhibited matched phylogeny with bee hosts, most of their phages showed a diminished level of cophylogeny. The evolutionary rates of the bee, the gut bacteria and the gut phages showed a remarkably increasing trend, including synonymous and non-synonymous substitution and gene content variation. For all of the three codiversified tripartite members, however, their genes under positive selection and genes involving gain/loss during evolution simultaneously enriched the functions into metabolism of nutrients, therefore highlighting the tripartite coevolution that results in an enhanced ecological fitness for the whole holobiont.

Abstract Background Previous studies have shown that the addition of platinum to neoadjuvant chemotherapy (NAC) improved outcomes for patients with triple-negative breast cancer (TNBC). However, no studies have assessed the efficacy and safety of the combination of taxane and lobaplatin. In this study, we conducted a randomized controlled phase II clinical study to compare the efficacy and safety of taxane combined with lobaplatin or anthracycline. Methods We randomly allocated patients with stage I–III TNBC into Arm A and Arm B. Arm A received six cycles of taxane combined with lobaplatin (TL). Arm B received six cycles of taxane combined with anthracycline and cyclophosphamide (TEC) or eight cycles of anthracycline combined with cyclophosphamide and sequential use of taxane (EC-T). Both Arms underwent surgery after NAC. The primary endpoint was the pathologic complete response (pCR). Secondary endpoints were event-free survival (EFS), overall survival (OS), and safety. Results A total of 103 patients (51 in Arm A and 52 in Arm B) were assessed. The pCR rate of Arm A was significantly higher than that of Arm B (41.2% vs. 21.2%, P = 0.028). Patients with positive lymph nodes and low neutrophil-to-lymphocyte ratio (NLR) benefited significantly more from Arm A than those with negative lymph nodes and high NLR (P interaction = 0.001, P interaction = 0.012, respectively). There was no significant difference in EFS (P = 0.895) or OS (P = 0.633) between the two arms. The prevalence of grade-3/4 anemia was higher in Arm A (P = 0.015), and the prevalence of grade-3/4 neutropenia was higher in Arm B (P = 0.044). Conclusions Neoadjuvant taxane plus lobaplatin has shown better efficacy than taxane plus anthracycline, and both regimens have similar toxicity profiles. This trial may provide a reference for a better combination strategy of immunotherapy in NAC for TNBC in the future.

ABSTRACT Recurrent C. difficile infection (rCDI) is an urgent public health threat, for which the last resort and lifesaving treatment is a fecal microbiota transplant (FMT). However, the exact mechanisms that mediate a successful FMT are not well-understood. Here, we use longitudinal stool samples collected from patients undergoing FMT to evaluate intra-individual changes in the microbiome, metabolome, and lipidome after successful FMTs relative to their baselines pre-FMT. We show changes in the abundance of many lipids, specifically a decrease in acylcarnitines post-FMT, and a shift from conjugated bile acids pre-FMT to deconjugated secondary bile acids post-FMT. These changes correlate with a decrease in Enterobacteriaceae, which encode carnitine metabolism genes, and an increase in Lachnospiraceae, which encode bile acid altering genes such as bile salt hydrolases (BSHs) and the bile acid-inducible (bai) operon, post-FMT. We also show changes in gut microbe-encoded amino acid biosynthesis genes, of which Enterobacteriaceae was the primary contributor to amino acids C. difficile is auxotrophic for. Liquid chromatography, ion mobility spectrometry, and mass spectrometry (LC-IMS-MS) revealed a shift from microbial conjugation of primary bile acids pre-FMT to secondary bile acids post-FMT. Here, we define the structural and functional changes associated with a successful FMT and generate hypotheses that require further experimental validation. This information is meant to help guide the development of new microbiota-focused therapeutics to treat rCDI.IMPORTANCERecurrent C. difficile infection is an urgent public health threat, for which the last resort and lifesaving treatment is a fecal microbiota transplant. However, the exact mechanisms that mediate a successful FMT are not well-understood. Here, we show changes in the abundance of many lipids, specifically acylcarnitines and bile acids, in response to FMT. These changes correlate with Enterobacteriaceae pre-FMT, which encodes carnitine metabolism genes, and Lachnospiraceae post-FMT, which encodes bile salt hydrolases and baiA genes. There was also a shift from microbial conjugation of primary bile acids pre-FMT to secondary bile acids post-FMT. Here, we define the structural and functional changes associated with a successful FMT, which we hope will help aid in the development of new microbiota-focused therapeutics to treat rCDI.

Abstract Honey authentication and traceability are crucial not only for economic purposes but also for ensuring safety. However, the widespread adoption of cutting-edge technologies in practical applications has been hampered by complex, time-consuming sample pre-treatment processes, the need for skilled personnel, and substantial associated expenses. This study aimed to develop a simple and cost-effective molecular technique to verify the entomological source of honey. By utilizing newly designed primers, we successfully amplified the mitochondrial 16S ribosomal RNA gene of honey bees from honey, confirming the high quality of the extracted DNA. Employing RFLP analysis with AseI endonuclease, species-specific restriction patterns were generated for honey derived from six closely related honey bees of the Apis genus. Remarkably, this method was proven equally effective in identifying heat-treated and aged honey by presenting the same RFLP profiles as raw honey. As far as we know, this is the initial research of the simultaneous differentiation of honey from closely related honey bee species using the restriction endonuclease AseI and mitochondrial 16S rRNA gene fragments. As a result, it holds tremendous potential as a standardized guideline for regulatory agencies to ascertain the insect origins of honey and achieve comprehensive traceability.

BackgroundAminoglycoside-modifying enzymes (AMEs) play an essential role in bacterial resistance to aminoglycoside antimicrobials. With the development of sequencing techniques, more bacterial genomes have been sequenced, which has aided in the discovery of an increasing number of novel resistance mechanisms.MethodsThe bacterial species was identified by 16S rRNA gene homology and average nucleotide identity (ANI) analyses. The minimum inhibitory concentration (MIC) of each antimicrobial was determined by the agar dilution method. The protein was expressed with the pCold I vector in E. coli BL21, and enzyme kinetic parameters were examined. The whole-genome sequence of the bacterium was obtained via the Illumina and PacBio sequencing platforms. Reconstruction of the phylogenetic tree, identification of conserved functional residues, and gene context analysis were performed using the corresponding bioinformatic techniques.ResultsA novel aminoglycoside resistance gene, designated aph(3’)-Ie, which confers resistance to ribostamycin, kanamycin, sisomicin and paromomycin, was identified in the chromosome of the animal bacterium Citrobacter gillenii DW61, which exhibited a multidrug resistance phenotype. APH(3’)-Ie showed the highest amino acid identity of 74.90% with the functionally characterized enzyme APH(3’)-Ia. Enzyme kinetics analysis demonstrated that it had phosphorylation activity toward four aminoglycoside substrates, exhibiting the highest affinity (Km, 4.22 ± 0.88 µM) and the highest catalytic efficiency [kcat/Km, (32.27 ± 8.14) × 104] for ribomycin. Similar to the other APH(3’) proteins, APH(3’)-Ie contained all the conserved functional sites of the APH family. The aph(3’)-Ie homologous genes were present in C. gillenii isolates from different sources, including some of clinical significance.ConclusionIn this work, a novel chromosomal aminoglycoside resistance gene, designated aph(3’)-Ie, conferring resistance to aminoglycoside antimicrobials, was identified in a rabbit isolate C. gillenii DW61. The elucidation of the novel resistance mechanism will aid in the effective treatment of infections caused by pathogens carrying such resistance genes.

In order to find a simpler method to simulate the charging of spacecraft surface and further analyze the characteristics of the charging reaction of low-orbit spacecraft surface materials, this paper uses COMSOL to perform finite element analysis on the charging of low-orbit spacecraft surface materials at an altitude of 300–400 km. First, the surface charging potential is established using the particle transport equation. By calculating the thermal diffusion movement of particles, the adsorption, secondary electron emission and backscattering effects of the material surface are evaluated to simulate the charging potential of the spacecraft surface. The results show that COMSOL based on the plasma module can replace SPIS to simulate the charged properties of spacecraft surface materials, indicating that different physical properties of the material surface are attached with different magnitudes of potential and small potential differences; In addition, based on the particle transport equation, this paper obtains the surface charging results of the Kapton connector between the solar panel and the spacecraft body, which is prone to charging. This research content provides a simplified method and new direction for the simulation study of spacecraft surface charging.

κ-casein (CSN3) polymorphisms are closely related to productive performance and dairy processing performance. In this study, CSN3 3’UTR polymorphisms in Chinese Holstein cows (n = 50) and the effects of these polymorphisms on the gene expression of four caseins, the protein expression of κ-casein, the binding of microRNAs (miRNAs), and cow production performance were investigated. There were two main haplotypes for the CSN3 3’UTR in Chinese Holstein cows: Haplotype 1 (0 mutations, n = 16) and Haplotype 10 (a combination of 7 mutations, n = 17). The gene and protein expression levels of CSN3 in Haplotype 1 were significantly greater than those in Haplotype 10 (p < 0.05). The ability of bta-miR-708 to bind to the CSN3 3’UTR with Haplotype 10 was significantly greater than that with Haplotype 1 (p < 0.05), potentially explaining why the gene and protein expression of CSN3 with Haplotype 10 were lower than those with Haplotype 1. Dairy herd improvement (DHI) data, including 305-d milk production, fat-corrected milk, fat (%), protein (%), and fat/protein ratio, were not significantly different between the two haplotypes (p > 0.05). Results suggest that the two major CSN3 3’UTR polymorphisms in Chinese Holstein cows cause significant changes in CSN3 gene expression, CSN3 protein expression, and bta-miR-708 binding ability but no significant alterations in macroscopic DHI data. Therefore, CSN3 3’UTR polymorphisms should be investigated further.

The chemical composition and quality of honey are influenced by its botanical, geographic, and entomological origins, as well as climatic conditions. In this study, the physicochemical characteristics, microbial communities, and hydrocarbon compounds of honey produced by Apis mellifera, Apis cerana, Apis laboriosa, Apis dorsata, and Apis florea were elucidated. The physicochemical profile of the honey exhibited significant differences across species, including moisture content (18.27–23.66%), fructose (33.79–38.70%), maltose (1.10–1.93%), electrical conductivity (0.37–0.74 mS/cm), pH (3.36–3.72), diastase activity (4.50–29.97 diastase number), and color (37.90–102.47 mm). Microbial analysis revealed a significant abundance of lactic acid bacteria, particularly the Apilactobacillus genus in A. laboriosa honey and the Lactobacillus in A. florea honey, indicating significant probiotic potential. Chemometric methods, principal component analysis, hierarchical cluster analysis, and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to classify the honey samples based on the 12 beeswax-derived hydrocarbons. The OPLS-DA model demonstrated 100% accuracy in predicting the entomological origin of honey, indicating that specific hydrocarbons are reliable markers for honey classification.

Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), showing high infectiousness, resulted in an ongoing pandemic termed coronavirus disease 2019 (COVID-19). COVID-19 cases often experience acute respiratory distress syndrome, which has caused millions of deaths. Apart from triggering inflammatory and immune responses, many viral infections can cause programmed cell death in infected cells. Cell death mechanisms have a vital role in maintaining a suitable environment to achieve normal cell functionality. Nonetheless, these processes are dysregulated, potentially contributing to disease pathogenesis. Over the past decades, multiple cell death pathways are becoming better understood. Growing evidence suggests that the induction of cell death by the coronavirus may significantly contributes to viral infection and pathogenicity. However, the interaction of SARS-CoV-2 with cell death, together with its associated mechanisms, is yet to be elucidated. In this review, we summarize the existing evidence concerning the molecular modulation of cell death in SARS-CoV-2 infection as well as viral-host interactions, which may shed new light on antiviral therapy against SARS-CoV-2.

Summary: Background: Anlotinib is a new type of tyrosine kinase inhibitor that targets vascular endothelial growth factor receptors 1/2/3, platelet-derived growth factor receptors α/β, and fibroblast growth factor receptors 1–4 and c-Kit, with a broad spectrum of inhibitory effects on tumor angiogenesis and growth. It has been proven effective in HER2-negative metastatic breast cancer, but its efficacy in early-stage triple-negative breast cancer (TNBC) is unknown. This phase 2 study aims to evaluate the efficacy and safety of adding anlotinib to neoadjuvant chemotherapy in patients with TNBC. Methods: Patients with clinical stage II/III TNBC were treated with 5 cycles of anlotinib (12 mg, d1-14, q3w) plus 6 cycles of taxanes (docetaxel 75 mg/m2 ,d1, q3w or nab-paclitaxel 125 mg/m2, d1 and d8, q3w) and lobaplatin (30 mg/m2, d1, q3w), followed by surgery. The primary endpoint was pathological complete response (pCR; ypT0/is ypN0) and the secondary endpoints include breast pCR (bpCR), axillary pCR (apCR), residual cancer burden (RCB), objective response rate (ORR), survival, and safety. Exploratory endpoints were efficacy biomarkers based on Fudan University Shanghai Cancer Center Immunohistochemical (FUSCC IHC) classification for TNBC and next-generation sequencing (NGS) of DNA from tumor tissue and blood samples of patients with 425-gene panel. This trial is registered with www.chictr.org.cn (ChiCTR2100043027). Findings: From Jan 2021 to Aug 2022, 48 patients were assessed and 45 were enrolled. All patients received at least one dose of study treatment and underwent surgery. The median age was 48.5 years (SD: 8.7), 71% were nodal involved, and 20% had stage III. In the intention-to-treat population, 26 out of 45 patients achieved pCR (57.8%; 90% CI, 44.5%–70.3%), and 39 achieved residual cancer burden class 0-I (86.7%; 95% CI, 73.2%–94.9%). The bpCR and apCR rate were 64.4% (29/45) and 71.9% (23/32), respectively. No recurrence or metastasis occurred during the short-term follow-up. Based on the FUSCC IHC-based subtypes, the pCR rates were 68.8% (11/16) for immunomodulatory subtype, 58.3% (7/12) for basal-like immune-suppressed subtype and 33.3% (4/12) for luminal androgen receptor subtype, respectively. NGS revealed that the pCR were 77% (10/13) and 50% (14/28) in MYC-amplified and wild-type patients, respectively, and 78% (7/9) and 53% (17/32) in gBRCA1/2-mutated and wild-type patients, respectively. The median follow-up time of the study was 14.9 months (95% CI: 13.5–16.3 months). There was no disease progression or death during neoadjuvant therapy. No deaths occurred during postoperative follow-up. In the safety population (N = 45), Grade 3 or 4 treatment emergent adverse events occurred in 29 patients (64%), and the most common events were neutropenia (38%), leukopenia (27%), thrombocytopenia (25%), anemia (13%), and hypertension (13%), respectively. Interpretation: The addition of anlotinib to neoadjuvant chemotherapy showed manageable toxicity and encouraging antitumor activity for patients with clinical stage II/III TNBC. Funding: Chongqing Talents Project, Chongqing Key Project of Technology Innovation and Application Development and Chongqing Outstanding Youth Natural Science Foundation.

In order to investigate the effect of endogenous components on the digestive characteristics of multigrain mixed noodles with low glycemic index (GI), the noodles were first prepared from buckwheat, yam, high-amylose corn starch and wheat flour, and the GI value was 53.02. On this basis, the endogenous components such as phenols, lipids, proteins and dietary fibres were removed from the raw flour of noodles and then prepared separately into noodles for in vitro simulated digestion. The effects of the endogenous components on the starch hydrolysis rate, protein digestibility and colonic fermentation of the noodles were investigated, as well as their mechanisms of action. The results showed that the starch hydrolysis rate of noodles prepared after the separation of endogenous components increased significantly, and the estimated glycemic index (eGI) was as follows: Defatted noodles (68.76)>deproteinised noodles (67.94)>dietary-fiber-free noodles (63.62)>dephenolised noodles (60.16)>low GI noodles (53.02). The protein digestibility of noodles was as follows: Dietary-fiber-free noodles (65.04%)>low GI noodles (33.71%)>dephenolised noodles (17.55%)>defatted noodles (6.61%). Compared with wheat noodles, the resistant starch in multigrain mixed with low GI noodles significantly increased the content of short-chain fatty acids (SCFAs) in colonic fermentation stage, which contributed to the host's regulation of glucolipid metabolism, energy metabolism and energy supply.

Abstract The objective of this multicenter, single‐arm trial (ChiCTR1900022293) was to explore the efficacy and safety of neoadjuvant therapy with epirubicin, cyclophosphamide, and pyrotinib followed by docetaxel, trastuzumab, and pyrotinib (ECPy‐THPy) in the treatment of patients with stage II–III HER2‐positive breast cancer. The present study enrolled patients with stage II–III HER2‐positive breast cancer. Epirubicin and cyclophosphamide were administrated for four 21‐day cycles, followed by four cycles of docetaxel and trastuzumab. Pyrotinib was taken orally once per day throughout the treatment period. The primary endpoint was total pathological complete response (tpCR, ypT0/is ypN0) rate in the modified intention‐to‐treat (mITT) population. In total, 175 patients were included. The tpCR rate was 68.6% (95% CI, 60.7–75.8%), while the objective response rate was 89.1%. In the post‐hoc subgroup analysis, no association between clinical characteristics and the tpCR rate was observed. The most common grade ≥3 adverse events were diarrhea (54.3%), followed by white blood cell count decreased (5.1%), and neutrophil count decreased (4.6%). In conclusion, the neoadjuvant regimen with ECPy‐THPy showed promising pathological response and clinical benefits with an acceptable safety profile in patients with stage II–III HER2‐positive breast cancer.

Royal jelly is a yellowish, creamy and acidic substance secreted by mandibular and hypopharyngeal glands of young worker bees. Fatty acids including (E)-10-hydroxy-2-decenoic acid, 10-hydroxydecanoic acid, 3,10-dihydroxydecanoic acid, 8-hydroxyoctanoic acid, sebacic acid and so on are one of the major components of royal jelly with a variety of biological activities, such as anti-inflammation, anti-bacteria and anti-tumor. Fatty acids are one of the main active components of royal jelly which are considered an important indicator in quality control. This article summarizes the identification methods of the royal jelly fatty acid including the principle of the method, the comparisons of technology and application features of methods, as well as the future research prospects. This review will provide a reference for the development of determining methods for fatty acids and pave the way for quality control of royal jelly.

Using subcritical sesame protein powder as the main raw material, the twin-screw extrusion technology was used to study the effect of extrusion texturing on the physicochemical properties and structure of protein raw materials, and to explore the formation mechanism of texturized protein. After extrusion, the water retention of protein materials increased by 14.16%, oil absorption decreased by 14.52%, protein digestibility increased by 11.18%, free sulfhydryl content decreased by 11.55%, and amino acid components had a certain loss. No new peptide bonds were formed during the extrusion texturing process, but a large number of disulfide bonds were formed. The structure of the texturized protein obtained by extrusion was mainly maintained by the combined action of disulfide bonds and non-covalent bonds. And the extrusion organization was not completely destroyed. The secondary structure of protein included only partially unstable α-helices and irregular coils to relatively stable β-sheets and β-turns. It could be seen that the protein material changed from disorder to order after extrusion and organization. And produced a large number of fiber structures. It would provide a theoretical basis for further study on the formation mechanism of histochemical proteins and development of histochemical sesame protein products.

BackgroundAeromonas species have been identified as agents responsible for various diseases in both humans and animals. Multidrug-resistant Aeromonas strains pose a significant public health threat due to their emergence and spread in clinical settings and the environment. The aim of this study was to determine a novel resistance mechanism against aminoglycoside antimicrobials in a clinical isolate.MethodsThe function of aac(6′)-Va was verified by gene cloning and antibiotic susceptibility tests. To explore the in vivo activity of the enzyme, recombinant proteins were expressed, and enzyme kinetics were tested. To determine the molecular background and mechanism of aac(6′)-Va, whole-genome sequencing and bioinformatic analysis were performed.ResultsThe novel aminoglycoside N-acetyltransferase gene aac(6′)-Va confers resistance to several aminoglycosides. Among the antimicrobials tested, ribostamycin showed the highest increase (128-fold) in the minimum inhibitory concentration (MIC) compared with the control strains. According to the MIC results of the cloned aac(6′)-Va, AAC(6′)-Va also showed the highest catalytic efficiency for ribostamycin [kcat/Km ratio = (3.35 ± 0.17) × 104 M−1 s−1]. Sharing the highest amino acid identity of 54.68% with AAC(6′)-VaIc, the novel aminoglycoside N-acetyltransferase constituted a new branch of the AAC(6′) family due to its different resistance profiles. The gene context of aac(6′)-Va and its close relatives was conserved in the genomes of species of the genus Aeromonas.ConclusionThe novel resistance gene aac(6′)-Va confers resistance to several aminoglycosides, especially ribostamycin. Our finding of a novel resistance gene in clinical A. hydrophila will help us develop more effective treatments for this pathogen’s infections.

BackgroundAchromobacter is a genus of gram-negative bacteria that can act as opportunistic pathogens. Recent studies have revealed that some species of Achromobacter show inherent resistance to β-lactams, but the resistance mechanisms of Achromobacter mucicolens have rarely been reported.MethodThe bacterium was isolated using standard laboratory procedures. The agar dilution method was used to determine the minimum inhibitory concentrations (MICs). Genome sequencing was performed using the PacBio RS II and Illumina HiSeq 2500 platforms, and the Comprehensive Antibiotic Resistance Database (CARD) was used to annotate the drug resistance genes. The localization of the novel β-lactamase AMZ-1 was determined, and its characteristics were determined via molecular cloning and enzyme kinetic analysis. The phylogenetic relationship and comparative genomic analysis of the resistance gene-related sequences were also analyzed.ResultAchromobacter mucicolens Y3, isolated from a goose on a farm in Wenzhou, showed resistance to multiple antibiotics, including penicillins and cephalosporins. BlaAMZ–1 showed resistance to amoxicillin, penicillin G, ampicillin, cephalothin and cefoxitin, and the resistance activity could be inhibited by β-lactamase inhibitors. Enzyme kinetic analysis results showed that AMZ-1 has hydrolytic activity against a wide range of substrates, including cephalothin, amoxicillin, penicillin G, and cefoxitin but not ampicillin. The hydrolytic activity of AMZ-1 was greatly inhibited by avibactam but much more weakly inhibited by tazobactam. Mobile genetic elements could not be found around the blaAMZ–1-like genes, which are conserved on the chromosomes of bacteria of the genus Achromobacter.ConclusionIn this study, a novel AmpC gene, blaAMZ–1, from the animal-origin bacterium A. mucicolens Y3 was identified and characterized. It conferred resistance to some penicillins and first- and second-generation cephalosporins. The identification of this novel resistance gene will be beneficial for the selection of effective antimicrobials to treat associated infections.

In answer to the demand for high sensitivity and miniaturization of ultra-high frequency (UHF) sensors for partial discharge (PD) detection in power equipment, this paper proposes research on miniaturized UHF-sensing technology for PD detection in power equipment based on symmetric cut theory. The symmetric cut theory is applied for the first time to the miniaturization of PD UHF sensors for power equipment. A planar monopole UHF sensor with a size of only 70 mm × 70 mm × 1.6 mm is developed using an exponential asymptotic feed line approach, which is a 50% size reduction. The frequency–response characteristics of the sensor are simulated, optimized and tested; the results show that the standing wave ratio of the sensor developed in this paper is less than 2 in the frequency band from 427 MHz to 1.54 GHz, and less than 5 in the frequency band from 300 MHz to 1.95 GHz; in the 300 MHz~1.5 GHz band; the maximum and average gains of the sensor E-plane are 4.76 dB and 1.02 dB, respectively. Finally, the PD simulation experiment platform for power equipment is built to test the sensor’s sensing performance; the results show that the sensor can effectively detect the PD signals; the sensing sensitivity is improved by about 95% relative to an elliptical monopole UHF sensor.

Baculovirus infection can prevent the pupation of insects. Juvenile hormone (JH) plays a vital role in regulating insect molting and metamorphosis. However, the molecular mechanism of baculovirus preventing the pupation of larvae by regulating the Juvenile hormone (JH) pathway is still unclear. In this study, we found that the Mamestra brassicae multiple nucleopolyhedroviruses (MbMNPV) infection prolonged the larval stage of fourth instar Helicoverpa armigera (H. armigera) by 0.52 d and caused an increase in JH titer. To identify the genes that contribute to the JH increase in H. armigera-MbMNPV interaction, we analyzed mRNA expression profiles of the fat bodies of H. armigera infected by MbMNPV. A total of 3637 differentially expressed mRNAs (DE-mRNAs) were filtered out through RNA-seq analysis. These DE-mRNAs were mainly enriched in Spliceosome, Ribosome biogenesis in eukaryotes, Aminoacyl-tRNA biosynthesis, Mismatch repair, and RNA degradation signaling pathway, which are related to the virus infection. Real-time PCR was used to verify the RNA sequencing results. To find out which genes caused the increase in JH titer, we analyzed all the DE-mRNAs in the transcriptome and found that the JHE and JHEH genes, which were related to JH degradation pathway, were down-regulated. JHE and JHEH genes in the larvae of MbMNPV-infected group were significantly down-regulated compared with the control group by RT-qPCR. We further proved that the JH is degraded by JHE in H. armigera larvae by RNAi, ELISA, RT-qPCR and bioassay, while the hydrolysis of JH by JHEH in H. armigera larvae can almost be ignored. Knocking down of HaJHE promoted the expression of the JH receptor gene Met and the downstream gene Kr-h1, and the replication of MbMNPV. This study clarified that JH is mainly degraded by JHE in H. armigera larvae. The MbMNPV infection of H. armigera larvae leads to the increase of JH titer by inhibiting the expression of JHE. The increase in JH titer promotes the expression of the JH receptor gene Met and the downstream gene Kr-h1, which prevents the pupation of H. armigera, and promotes MbMNPV replication. This study provides new insights into H. armigera and MbMNPV interaction mechanisms.

To explore the effect of saturated fatty acid carbon chain length on the structure and in vitro digestive properties of waxy wheat A and B starch-lipid complexes. Using waxy wheat A and B starch as the main raw materials, after being modified by compound enzymes, they were compounded with lauric acid, myristic acid, palmitic acid and stearic acid respectively, and the compound index (CI value), the solubility and swelling power, iodine absorption characteristics, crystal structure, fourier transform infrared spectroscopy and predicted glycemic index (pGI value) were investigated. The results showed that with the increasing of carbon chain (12~18), the CI values of starch-lipid complexes of waxy wheat A and B decreased from 53.66% to 38.15%, and from 60.35% to 41.04%. The solubility and swelling power of starch-lipid complexes of waxy wheat A and B increased gradually with the increasing of temperature and the number of carbon atoms. The solubility and swelling power of waxy wheat A starch-lauric acid at 90 ℃ were 1.99% and 3.34 g/g, the solubility and swelling power of waxy wheat B starch-lauric acid at 90 ℃ were 1.74% and 3.18 g/g respectively. Among the four lipid complexes, the complexes formed by waxy wheat starch A, B and lauric acid had relatively high crystallinity, reaching 25.37% and 23.50%, and their ratios at 1047/1022 cm−1 were also high, which were 0.993 and 0.989. Compared with the uncomplexed lipid-modified waxy wheat starch, the pGI values decreased significantly, from 47.63 to 36.61, and from 48.30 to 35.49 respectively. This study can provide a reference for the structure and in vitro digestion characteristics of starch-lipid complexes.

BackgroundAminoglycosides, as important clinical antimicrobials, are used as second-line drugs for treating multidrug-resistant tuberculosis or combined with β-lactam drugs for treating severe infections such as sepsis. Aminoglycoside-modifying enzyme (AME) is the most important mechanism of aminoglycoside resistance and deserves more attention.MethodsThe bacterium Kluyvera intermedia DW18 was isolated from the sewage of an animal farm using the conventional method. The agar dilution method was used to determine the minimum inhibitory concentrations (MICs) of antimicrobials. A novel resistance gene was cloned, and the enzyme was expressed. The kinetic parameters were measured by a SpectraMax M5 multifunctional microplate reader. Bioinformatic analysis was performed to reveal the genetic context of the aph(3′)-Id gene and its phylogenetic relationship with other AMEs.ResultsA novel aminoglycoside 3′-O-phosphotransferase gene designated aph(3′)-Id was identified in K. intermedia DW18 and shared the highest amino acid identity of 77.49% with the functionally characterized aminoglycoside 3′-O-phosphotransferase APH(3′)-Ia. The recombinant plasmid carrying the novel resistance gene (pMD19-aph(3′)-Id/E. coli DH5α) showed 1,024-, 512-, 128- and 16-fold increased MIC levels for kanamycin, ribostamycin, paromomycin and neomycin, respectively, compared with the reference strain DH5α. APH(3′)-Id showed the highest catalytic efficiency for ribostamycin [kcat/Km of (4.96 ± 1.63) × 105 M−1/s−1], followed by paromomycin [kcat/Km of (2.18 ± 0.21) × 105 M−1/s−1], neomycin [kcat/Km of (1.73 ± 0.20) × 105 M−1/s−1], and kanamycin [kcat/Km of (1.10 ± 0.18) × 105 M−1/s−1]. Three conserved functional domains of the aminoglycoside phosphotransferase family and ten amino acid residues responsible for the phosphorylation of kanamycin were found in the amino acid sequence of APH(3′)-Id. No mobile genetic element (MGE) was discovered surrounding the aph(3′)-Id gene.ConclusionIn this work, a novel aminoglycoside 3’-O-phosphotransferase gene designated aph(3′)-Id encoded in the chromosome of the environmental isolate Kluyvera intermedia DW18 was identified and characterized. These findings will help clinicians select effective antimicrobials to treat infections caused by pathogens with this kind of resistance gene.

BackgroundPantoea species of the family Erwiniaceae are well-known plant pathogens and animal and human conditional pathogens. Due to the widespread and continuous use of antimicrobials, multidrug-resistant strains continue to emerge, making clinical treatment difficult; therefore, there is an increasing need to clarify the mechanisms of drug resistance.MethodsA rabbit anal fecal sample was collected by a swab and the streak plate method was used to isolate single colonies. The standard agar dilution method was used to determine the minimum inhibitory concentrations (MICs) against antimicrobials. The complete genome sequence of the bacterium was obtained using Next-Generation Sequencing platforms. The potential resistance gene was annotated based on the Comprehensive Antibiotic Resistance Database (CARD) and verified by molecular cloning. The β-lactamase PSZ-1 was expressed via the pCold I expression vector and its enzyme kinetic parameters were analyzed. The genetic environment and evolutionary process of the novel resistance gene-related sequences were analyzed by bioinformatic methods.ResultsThe isolate Pantoea endophytica X85 showed some degree of resistance to penicillins as well as cephalosporins. A novel AmpC resistance gene, designated blaPSZ-1 in this research, was identified to be encoded in the plasmid (pPEX85) of P. endophytica X85. BlaPSZ-1 showed resistance to penicillins and several first-, second-and third-generation cephalosporins as well as aztreonam, but it did not show resistance to the fourth-generation cephalosporins or carbapenems tested. Enzyme kinetic assays revealed that it could hydrolyze amoxicillin, penicillin G, cephalothin, and cefazolin, and its hydrolytic activity could be strongly inhibited by the inhibitor avibactam, which was generally consistent with antimicrobial susceptibility testing results. No hydrolytic activity was observed for third-generation cephalosporins or aztreonam.ConclusionIn this study, a novel AmpC β-lactamase gene, designated blaPSZ-1, was characterized and it was encoded in the plasmid of the bacterium P. endophytica X85. It shows resistance to penicillins and several cephalosporins. The discovery of novel drug resistance mechanisms can help guide the scientific use of drugs in animal husbandry and clinical practice, effectively avoiding the abuse of antimicrobials and thus preventing the further development and spread of bacterial resistance.

Eusocial insects have evolved specific defensive strategies to protect their colonies. In termite colonies, soldiers perform a colony-level defense by displaying mechanical biting, head-banging and mandible opening–closing behaviors. However, few studies have been reported on the factors modulating defensive behaviors in termites. Owing to JH (juvenile hormone) being involved in soldier differentiation, JH was speculated to affect defensive behaviors in termite soldiers. To determine the effect of JH on the defensive behaviors of termite soldiers, we performed a JHA-feeding and RaSsp1-silencing experiment and then tested the changes in defense-related behaviors, alarm pheromones and key JH signaling genes. The observed result was that after feeding workers with JHA, soldiers displayed the following: (1) decreased biting events and increased head-banging events; (2) a reduced expression of RaSsp1 and increased expression of Met (methoprene-tolerant, the nuclear receptor of JH) and Kr-h1 (the JH-inducible transcription factor Krüppel homolog 1); and (3) a decreased concentration of alarm pheromones, including α-pinene, β-pinene and limonene (+, −). Further study showed that soldiers silenced for RaSsp1 also exhibited (1) decreased biting events and increased head-banging events and (2) increased expression of Met and Kr-h1. In addition, soldiers stimulated by the alarm pheromone limonene displayed an increase in the frequency of mandible opening–closing and biting behavior. All of these results show that JHA influenced the defensive behaviors of termite soldiers, possibly via downregulating RaSsp1 expression, up-regulating Met and Kr-h1 and stimulating the secretion of alarm pheromones, suggesting that the JH pathway plays important roles in modulating social behaviors in termite colonies.

This work employing the first-principles theory investigated the potential of Pd-doped PtSe2 (Pd–PtSe2) monolayer as a sensing material for detection of H2S and SOF2 in the SF6 insulation devices. The Pd dopant is stably trapped on the TPt site of the PtSe2 surface with Eb of −2.37 eV, and the bandgap of Pd–PtSe2 system is reduced to 0.81 eV from that of 1.31 eV of the pristine counterpart. Pd–PtSe2 monolayer has stronger adsorption performance upon SOF2 with Ead of −0.94 eV than H2S with Ead of −0.88 eV, leading to more obvious increase to 0.96 eV in the SOF2 system than that of 0.84 eV in the H2S system. Thus, the much higher sensitivity and more desirable recovery property give rise to the stronger suitability of Pd–PtSe2 monolayer for SOF2 detection, as verified by the I–V curve analysis wherein the electrical resistance and sensing response are seen much larger in the SOF2 system. Moreover, the applied strain is proved as a workable manner to modulate the sensing performance of Pd–PtSe2 monolayer, with tunable QT and Eg obtained in various strains. Our calculations evidence the potential of Pd–PtSe2 monolayer as a promising gas sensor to evaluate the operation status of the SF6 insulation devices, which is beneficial to stimulate more edge-cutting work in the field of gas sensing as well.

In this paper, we using the first-principles theory systemically investigate the geometric and electronic properties of the PtXY (X, Y = S, Se and Te) monolayers under the applied biaxial strains and electric fields. The optimized morphologies, deformation charge density, band structure and orbital DOS are plotted and analyzed. Our findings indicate that the applied biaxial strains can largely impact the morphologies of the PtXY systems while the electric fields do not. Given the remarkable charge-transfer crossing the X and Y planes caused by applied biaxial strains and electric field, the electronic property as well as the bandgap of the PtXY systems are modulated largely. It is conclude that PtSSe monolayer is a proper tensile sensing material while the PtSTe and PtSeTe monolayers are potential compressive sensing candidate. Meanwhile, PtSSe and PtSTe systems have desirable linear sensitivity to the applied electric field in terms of electrical conductivity, while the PtSeTe monolayer is only linearly sensitive for the negative electric field. The I-V analysis reveals the resistance property of the PtXY monolayers under various voltages and is consistent with the BS analysis. Our work uncover the physicochemical properties of the PtXY monolayer for typical applications and give the guidance to unfold a new orientation to explore novel semiconductor devices.

Breast cancer (BC) is the most commonly diagnosed cancer worldwide. Advanced BC with brain metastasis (BM) is a major cause of mortality with no specific or effective treatment. Therefore, better knowledge of the cellular and molecular mechanisms underlying breast cancer brain metastasis (BCBM) is crucial for developing novel therapeutic strategies and improving clinical outcomes. In this review, we focused on the latest advances and discuss the contribution of the molecular subtype of BC, the brain microenvironment, exosomes, miRNAs/lncRNAs, and genetic background in BCBM. The blood–brain barrier and blood–tumor barrier create challenges to brain drug delivery, and we specifically review novel approaches to bypass these barriers. Furthermore, we discuss the potential application of immunotherapies and genetic editing techniques based on CRISPR/Cas9 technology in treating BCBM. Emerging techniques and research findings continuously shape our views of BCBM and contribute to improvements in precision therapies and clinical outcomes.

Food safety and quality are paramount concerns for ensuring the preservation of human life and well-being. As the field of food processing continues to advance, there is a growing interest in the development of fast, instant, cost-effective, and convenient methods for detecting food safety issues. In this context, the utilization of paper-based microfluidic chips has emerged as a promising platform for enabling rapid detection, owing to their compact size, high throughput capabilities, affordability, and low resource consumption, among other advantages. To shed light on this topic, this review article focuses on the functionalization of paper-based microfluidic surfaces and provides an overview of the latest research and applications to colorimetric analysis, fluorescence analysis, surface-enhanced Raman spectroscopy, as well as their integration with paper-based microfluidic platforms for achieving swift and reliable food safety detection. Lastly, the article deliberates on the challenges these analytical methods and presents insights into their future development prospects in facilitating rapid food safety assessment.

Abstract The information of dissolved gas in transformer oil can reflect the potential fault in oil immersed power transformer. In order to improve the accuracy of transformer fault diagnosis, a transformer fault diagnosis model based on IFA‐LPboost‐CART is proposed here. First, a LPboost‐CART model is established. The classification and regression tree (CART) are used as the weak classifiers, and the linear programming boosting (LPboost) ensemble learning method is used to adjust the weight of each weak classifier to construct a strong classifier. Then the improved firefly algorithm (IFA) is adopted to optimize the number of CART and the maximum number of splits of CART in LPboost‐CART to obtain the IFA‐LPboost‐CART model. The experimental results show that, compared with the existing methods, such as CART and support vector machine (SVM), the proposed IFA‐LPboost‐CART model has higher fault diagnosis accuracy, which can provide technical support for transformer fault diagnosis.

The epoxy resin is the main solid insulating material for electrical equipment. PD (partial discharge) is an important factor leading to epoxy resin aging or failure. Fault detection technology based on audible acoustic imaging has the advantages of real-time monitoring, visibility, and flexibility and is gradually being used in the field of electrical equipment insulation state monitoring. However, the audible voiceprint features of epoxy resins with typical PD defects are not clear, which is not conducive to effective detection and fault diagnosis. Therefore, in this study, the study of audible voiceprint features of epoxy resins with a metal burr, pollution, metal foreign matters, and surface discharge defects was carried out. The discharge audible signals were obtained, and their time and frequency domain features were analyzed. The results show that the discharge audible signals of four PD defects can reflect the occurrence of PD simultaneously with pulse current signals. But the characteristics are obviously different in the time domain, which are embodied in listening perception, persistence, amplitude, and phase. In the frequency domain, the frequency spectra of discharge audible signals of four defects are mainly 5–10 and 13–24 kHz. Furthermore, the three feature vectors of frequency spectrum complexity, high-frequency energy factor, and maximum frequency point are extracted, which can well distinguish the discharge audible signals of four PD defects.

Breast cancer is the most common malignancy in women, and there is evidence for the dual role of cell pyroptosis in tumor development. However, little is known about the relationship between cell pyroptosis and breast cancer and its prognostic value. We aimed to construct a prognostic model using cell-pyroptosis-related genes to provide innovative insights into the prognosis and treatment of breast cancer. We screened candidate genes for pyroptosis using public databases and identified 10 cell pyroptosis signature genes with the random forest method. Finally, a nomogram for predicting 1-, 3-, and 5-year survival probabilities was constructed. The differences in immune cell distributions between survival periods were similar across the breast cancer datasets. The 10 identified key pyroptosis factors showed a significant correlation with Her2, tumor–node–metastasis (TNM) stage, and survival of breast cancer. The risk scores correlated positively with the infiltration features of naive B cells, CD8+ T cells, atpdelnd mast cells, while they correlated negatively with those of M0 macrophages and dendritic cells. In conclusion, our findings confirm that cell pyroptosis is closely associated with breast cancer. Importantly, the prognostic complex values generated from the 10 cell-pyroptosis-related genes based on various clinical features may provide an important basis for future studies on the prognosis of breast cancer.

To meet the real demand for broadband full-band high-gain antenna sensors in the process of partial discharge (PD) Ultra-High frequency (UHF) detection test and online monitoring of power equipment, this paper builds a resonant cavity monopole UHF antenna sensor based on Fabry–Perot resonant cavity antenna technology, conducts the sensor Voltage Standing Wave Ratio (VSWR) optimization study using curved flow technology, conducts the sensor gain optimization study using slot dual resonant structure, and, finally, tests the sensor performance using the built PD detection test platform. The resonant cavity monopole antenna exhibits outstanding VSWR performance in the frequency range of 0.37 GHz–3 GHz, according to simulation and test data: the average gain in the frequency range of 0.3 GHz–3 GHz is 4.92 dBi, and the highest gain at the primary resonant frequency of 1.0 GHz is 7.16 dBi, with good radiation performance over the whole frequency spectrum. The electromagnetic pulse signal sensed by the UHF sensor developed in this paper can demonstrate the energy spectrum distribution characteristics of PD radiation electromagnetic wave signal more comprehensively, laying a firm technical foundation for thoroughly understanding the electromagnetic wave radiation characteristics of various types of PD insulation defects of various power equipment and the selection of a specific direction for its supporting optimization.

The use of flexible, built-in, ultra-high-frequency (UHF) antenna sensors is an effective method to solve the weak high-frequency electromagnetic wave signal sensing of partial discharge (PD) inside gas-insulated switchgears (GISs), and the compatibility of flexible UHF antenna sensor substrate materials and SF6/N2 mixtures is the key to the realization of a flexible UHF antenna sensor inside a GIS. Based on this, this paper builds an experimental platform for the compatibility of a 30% SF6/70% N2 gas mixture and a PD flexible UHF antenna sensor substrate and conducts compatibility experiments between the 30% SF6/70% N2 gas mixture and PD flexible UHF antenna sensor substrate under different temperatures in combination with the actual operating temperature range of the GIS. In this article, a Fourier transform infrared spectrometer, scanning electron microscope and X-ray photoelectron spectrometer were used to test and analyze the gas composition, the surface morphology and the elemental change in the PD flexible UHF antenna sensor substrate, respectively. PET material will be slightly oxidized under the environment of a 30% SF6/70% N2 gas mixture at 110 °C, PI material will generate metal fluoride under the environment of a 30% SF6/70% N2 gas mixture and only PDMS material will remain stable under the environment of a 30% SF6/70% N2 gas mixture; therefore, it is appropriate to use PDMS substrate in the development of flexible UHF antenna sensors.

Background: Hepatocellular carcinoma (HCC) is notorious for its high mortality and incidence. Accumulating evidence confirms that chromatin regulators (CRs) have a significant impact on cancer. Therefore, exploring the mode of action and prognostic value of CRs is imminent for the treatment of hepatocellular carcinoma.Method: Transcriptome and clinical data for this study have been downloaded from TCGA (https://portal.gdc.cancer.gov/) and ICGC (https://dcc.icgc.org/). Univariate analysis was used to screen CRs with prognostic value, and our prognostic risk score signature was developed using least absolute shrinkage along with selection operator (lasso) Cox regression analysis. The CRs-based prognostic model was constructed in the TCGA dataset, and low-risk HCC patients had a better prognosis, which was finally validated in the ICGC dataset. We used the receiver operating characteristic curve to identify the accuracy of the prediction model and establish a line chart to prove the clinical effectiveness of the model. We also discussed the differences in drug sensitivity via CellMiner database, tumor immune microenvironment via ssGSEA algorithm, and clinical characteristics among different risk groups.Results: A prognostic model consisting of seven CRs was constructed and verified in HCC patients. Furthermore, we found that this risk score prognostic signature could independently predict the prognosis of HCC patients. Functional enrichment analysis revealed that CRs are mainly associated with cancer-related signaling pathways and metabolic pathways. In addition, immune cell abundance correlates with risk score levelsConclusion: In brief, we systematically explored the mode of action of CRs in HCC patients and established a reliable prognostic prediction model.

To investigate the decomposition law of SF6 under negative direct current partial discharge (PD) at different energies, a SF6 PD hybrid numerical model based on fluid dynamics and plasma chemical reaction models, in which 14 particle species and 24 chemical reactions are considered, is proposed. The effectiveness of the proposed model is validated with the current pulse waveform and the V–I discharge curve obtained by experiment. The influence of discharge energy on SF6 PD characteristic quantities and SF6 decomposition products is investigated with simulation and experiment. The results show that most of the discharge area of SF6 is neutral, and the cation clouds only exist in the ionosphere (4.79–5 mm). With the increase in applied voltage, the electric field intensity of the needle plate gap does not increase completely and even decreases in some areas. Moreover, different from the traditional opinion, the generation of SO2F2 under PD is mainly generated by the hydrolysis reaction of SOF4, which is formed by [SF5], [SF4], and [OH], [O]. The reaction path of [SF2] with O2 is not important. Thus, c(SO2F2)/c(SOF2 + SO2) can be used as the energy characteristic component ratio because of its ability to represent the low-fluorine sulfide ratio n([SF5])/n([SF4]).

Spiral antenna sensors are commonly used in partial discharge (PD) ultra-high frequency (UHF) detection in gas-insulated switchgears (GISs). However, most of the existing UHF spiral antenna sensors are based on a rigid base and balun, such as FR-4. The safe built-in installation of antenna sensors requires the complex structural transformation of GISs. To solve this problem, a low-profile spiral antenna sensor is designed based on a polyimide (PI) flexible base, and its performance is optimized by improving the clearance ratio. The simulation and measurement results show that the profile height and diameter of the designed antenna sensor is 0.3 mm and 137 mm, which is 99.7% and 25.4% smaller than the traditional spiral antenna. Under a different bending radius, the antenna sensor can maintain VSWR ≤ 5 in 650 MHz~3 GHz, and its maximum gre is up to 6.1 dB. Finally, the PD detection performance of the antenna sensor is carried out on a real 220 kV GIS. The results show that, after being built in, the PD with a weak discharge magnitude of 4.5 pC can be effectively detected by the antenna sensor, and the antenna sensor has the ability to quantify the severity of PD. In addition, through the simulation, the antenna sensor has potential for the detection of micro water in GISs.

It is essential to understand the mechanism of action of ultrasound synergistic free radical oxidation to promote covalent reactions between proteins and polyphenols. (−)-epigallo-catechin 3-gallate (EGCG) with rich bioactivity could be used to increase the functional properties of cereal protein—gliadin (GL). This study systematically explored the role of ultrasound treatment (US) on the binding mechanisms of GL and EGCG. Electrophoresis and high-performance liquid chromatography (HPLC) confirmed the greater molecular mass of the covalent complexes in the ultrasound environment. Quantitative analysis by the phenol content revealed that the ultrasound environment increased the EGCG content in the covalent complex by 15.08 mg/g of protein. The changes in the spatial structure of the proteins were indicated by Fourier infrared and ultraviolet spectroscopy. Additionally, scanning electron microscopy (SEM) and atomic force microscopy (AFM) found that US disrupted the aggregation of GL and the clustered structure of the covalent complexes. The results demonstrated that the water solubility of ultrasonic conjugates was significantly increased by 8.8–64.19%, the digestion rate was more efficient, and the radical scavenging capacity was twice that of GL. This research contributes to the theoretical basis for broadening the application of polyphenols in modifying protein.

The audible signal (20 Hz to 20 kHz) generated during the operation of a dry-type reactor is one of the key features to evaluate its operation state. However, at present, the time/frequency domain features of the audible signal under typical insulation defects are not clear, which makes it difficult to effectively carry out the fault diagnosis of the dry-type reactor based on audible signals. Based on this, the audible signal features under typical insulation defect discharge of the dry-type reactor are studied in this paper. Three typical insulation defect discharge models (metal protrusion defect, pollution defect, and metal foreign bodies defect) are simulated; then, the discharge acoustic signals are collected under the voltage of 8 kV. Analysis of acoustic signal features shows that the acoustic signal of metal protrusion defect discharge occurs in the positive half cycle of power frequency with the cycle of 20 ms. Both pollution defect discharge and metal foreign bodies defect discharge show intermittent discharge; during the discharge, the discharge acoustic signal of pollution defect has features similar to that of metal protrusion defect, while the discharge of metal foreign bodies defect shows randomness with a larger amplitude of discharge acoustic signal (up to 110 dB). Based on the frequency domain feature vectors’ extraction, it is found that the odd harmonic component of the metal protrusion defect discharge acoustic signal accounts for more than twice the even-order harmonic, and the high-frequency energy (12.5–25 kHz) is the main component. The discharge acoustic signal of the metal foreign bodies defect is mainly low-frequency energy, and the high-frequency energy proportion of pollution defect discharge acoustic signal is similar to that of low-frequency energy. In addition, the variance of high-frequency energy ratio (Rhf) of the metal foreign bodies defect discharge acoustic signal is 5.25 and 21 times that of the metal protrusion defect and pollution defect. This study provides some technical support for further detection and assessment of the operation state of the dry-type reactor based on audible signals.

Food adulteration is a serious problem all over the world. Establishing an accurate, sensitive and fast detection method is an important part of identifying food adulteration. Herein, a sequence-specific ladder-shape melting temperature isothermal amplification (LMTIA) assay was reported to detect soybean-derived components using proofreading enzyme-mediated probe cleavage (named Proofman), which could realize real-time and visual detection without uncapping. The results showed that, under the optimal temperature of 57 °C, the established Proofman–LMTIA method for the detection of soybean-derived components in dairy products was sensitive to 1 pg/μL, with strong specificity, and could distinguish soybean genes from those of beef, mutton, sunflower, corn, walnut, etc. The established Proofman–LMTIA detection method was applied to the detection of actual samples of cow milk and goat milk. The results showed that the method was accurate, stable and reliable, and the detection results were not affected by a complex matrix without false positives or false negatives. It was proved that the method could be used for the detection and identification of soybean-derived components in actual dairy products samples.

MicroRNAs (miRNAs), are a novel class of gene expression regulators, that have been found to participate in regulating host–virus interactions. However, the function of insect-derived miRNAs in response to virus infection is poorly understood. We analyzed miRNA expression profiles in the fat bodies of Helicoverpa armigera (H. armigera) infected with Mamestra brassicae multiple nucleopolyhedroviruses (MbMNPV). A total of 52 differentially expressed miRNAs (DEmiRNAs) were filtered out through RNA-seq analysis. The targets of 52 DEmiRNAs were predicted and 100 miRNA–mRNA interaction pairs were obtained. The predicted targets of DEmiRNAs were mainly enriched in the Wnt signaling pathway, phagosome, and mTOR signaling pathway, which are related to the virus infection. Real-time PCR was used to verify the RNA sequencing results. ame-miR-317-3p, mse-miR-34, novel1-star, and sfr-miR-6094-5p were shown to be involved in the host response to MbMNPV infection. Results suggest that sfr-miR-6094-5p can negatively regulate the expression of four host genes eIF3-S7, CG7583, CG16901, and btf314, and inhibited MbMNPV infection significantly. Further studies showed that RNAi-mediated knockdown of eIF3-S7 inhibited the MbMNPV infection. These findings suggest that sfr-miR-6094-5p inhibits MbMNPV infection by negatively regulating the expression of eIF3-S7. This study provides new insights into MbMNPV and H. armigera interaction mechanisms.

The aim of this study was to investigate the changes in protein, antioxidant activity, and starch of two varieties of green wheat and wheat in vitro simulated digestion. The experiment was used a new in vitro simulated digestion process which was closer to the body’s digestive system. The protein utilization of green wheat in the beginning of digestion was lower than that of wheat. However, in the intestinal stage, it was slightly higher than wheat to reach. The total phenolic, flavonoid content and DPPH radical scavenging power of green wheat were about twice that of wheat. The antioxidant activity of green wheat was stronger than that of wheat. Although the glucose content of green wheat was higher than wheat, the GI of green wheat (52–54) was always much lower than wheat (65–71). Therefore, the appropriate replacement of wheat with green wheat as the main food is more conducive to the absorption of nutrients, the use of antioxidant activity and the regulation of blood glucose.

Mo2C is a two-dimensional material with high electrical conductivity, low power consumption, and catalytic effect, which has promising applications in the field of microfluidic gas detection. First principles were used to study the adsorption characteristics of Mo2C monolayer on four typical decomposition gases of SF6 (H2S, SO2, SOF2, and SO2F2), and to explore the feasibility of its application in the detection of SF6 decomposition components. The results showed that Mo2C chemisorbed all four gases, and the adsorption capacity was H2S < SO2 < SOF2 < SO2F2. The adsorption mechanism of Mo2C as a microfluidic sensor was analyzed in combination with its charge-density difference and density of states. On the other hand, the different work-function change trends after adsorbing gases provide the possibility for Mo2C to selectively detect gases as a low-power field-effect transistor sensor. All content can be used as theoretical guidance in the realization of Mo2C as a gas-sensitive material for the detection of SF6 decomposition components.

In view of the insufficient signal detection sensitivity of Gas Insulated Switchgear (GIS), partial discharge (PD), ultra-high frequency (UHF), and failure to conform with GIS surface structure when the existing rigid stereo structure UHF sensor is built in, this paper, using rectangular patch antenna equivalent technique, trapezoidal ground plane technique, and coplanar waveguide (CPW) feed line index asymptotic linearization technique, conducts research on a flexible built-in high-sensitivity elliptic monopole antenna. The flexible antenna, with a thickness of only 0.28 mm, can be kept at a voltage standing wave ratio (VSWR) of less than three in the 300 MHz to 3 GHz band under the curvature radius of 0, 100, 300, and 500 mm, and at less than two in the 650 MHz to 3 GHz band. Through the true 220 kV-GIS partial discharge experimental platform built to analyze the high frequency electromagnetic wave detection performance of the built-in flexible antenna, it is shown that the flexible built-in high-sensitivity elliptical monopole antenna designed in this paper can effectively detect the characteristic signals of high-frequency electromagnetic waves emitted by partial discharges with an average discharge amount below 10 pC.

In this paper, the first-principles theory is used to explore the adsorption behavior of Ni catalyst decorated PtSe2 (Ni-PtSe2) monolayer toward the dissolved gas in transformer oil, namely CO and C2H2. Some Ni atoms from the catalyst are trapped in the Se vacancy on the pure PtSe2 surface. The geometry configurations of Ni-PtSe2 monolayer before and after gas adsorption, the electronic property of Ni-PtSe2 monolayer upon gas adsorption, and the sensibility and recovery property of Ni-PtSe2 monolayer are explored in this theoretical work. Through the simulation, the Ead of CO and C2H2 gas adsorption systems are calculated as −1.583 eV and −1.319 eV, respectively, both identified as chemisorption and implying the stronger performance of the Ni-PtSe2 monolayer on CO molecule, which is further supported by the DOS and BS analysis. According to the formula, the sensitivity of Ni-PtSe2 monolayer towards CO and C2H2 detection can reach up to 96.74% and 99.91% at room temperature (298 K), respectively, which manifests the favorable sensing property of these gases as a chemical resistance-type sensor. Recovery behavior indicates that the Ni-PtSe2 monolayer is a satisfied gas scavenger upon the noxious gas dissolved in transformer oil, but its recovery time at room temperature is not satisfactory. To sum up, we monitor the status of the transformer to guarantee the stable operation of the power system through the Ni-PtSe2 monolayer upon the detection of CO and C2H2, which may realize related applications, and provide the basis and reference to cutting-edge research in the field of electricity in the future.

In this paper, the authors studied five characteristics of green wheat starch, including amylose and damage starch content, morphology, relative crystallinity, crystallinity pattern and pasting properties. The amylose and damaged starch content varied from 14.57 to 21.00%, and 5.2 to 11.96%, respectively. Green wheat starch exhibited granules oblate, elliptical, round and slightly different from wheat starch. The starches were categorized based on crystal types into A starches and the crystallinity ranges from 19.81 to 28.20%. The starches exhibited a pasting temperature of 81.05–87.55°C, peak viscosity of 12.57–29.05 P, and setback value of 5.67–14.73 P. In addition, we used thermogravimetric-fourier transform infrared spectroscopy (TG-FTIR) to determine the starch content of green wheat starch. The characteristic decomposition temperature range of starch in green wheat was determined by TG to be 225–375°C, and verified by infrared absorption spectroscopy. Starch content of the five green wheat samples was determined by AACC 76–13 and TG method. The results of precision and accuracy test showed that there was no significant difference in the starch content of the green wheat obtained by the two methods.

C5F10O (C5 perfluorinatedketone) has received extensive attention due to its great insulation and eco-friendly performance, which has the potential to replace SF6 usage in power industries. In this paper, the power-frequency breakdown properties and discharge decomposition characteristics of C5F10O/Air and C5F10O/N2 gas mixtures are explored. It is found that the AC breakdown voltage of the C5F10O gas mixtures increases gradually with both the gas pressure and the content of C5F10O. As the partial pressure of C5F10O increases, the relative insulation strength increasing trend of the C5F10O gas mixtures becomes less obvious with the increase in the gas pressure. The AC breakdown voltage of the C5F10O/Air gas mixture is higher than that of the C5F10O/N2 gas mixture. In addition, the decomposition products of the C5F10O gas mixtures are mainly CF4, C2F6, C3F8, C4F10, and C3F7H. Under the same condition, the content of the CF4 in C5F10O/Air gas mixture is higher than that of the C5F10O/N2 gas mixture. The decomposition of the C5F10O/Air gas mixture after breakdown did not produce C2F4 and C3F6. CF2O and CO2 are not detected in the C5F10O/N2 gas mixture. Moreover, the carbon precipitation on the electrodes' surface can be found for the C5F10O/N2 gas mixture after 60 breakdown tests.

C6F12O can be used in gas-insulated equipment due to its excellent insulation properties. The purpose of this paper is to calculate the total electron-impact ionization cross section to evaluate the dielectric strength of the molecule using the Deutsch–Märk formula. First, according to the calculation method of quantum chemistry, the structure of the molecule is optimized. Three different methods, such as Mulliken population analysis, C-squared population analysis, and natural atomic orbital (NAO), are used to calculate the molecular orbital components, and then the molecular collision cross section is obtained. The influence of different weighting factors on the calculation results is analyzed. The validity of the proposed method is verified by the calculation results of H2O, C3H6O, and C5F10O. The results show that the calculation value with the NAO method is closer to the experimental results, which provides a reference for the calculation and analysis of the collision cross section of C6F12O. The calculation results in this paper can provide basic data for further calculation of the dielectric strength of C6F12O.

To address the problem of low space utilization of existing rigid Ultra-High Frequency (UHF) sensors for partial discharge (PD) in Gas-Insulated Switchgears (GIS) and the problem of disrupting the electric field distribution inside the GIS. This paper draws on the idea of flexible wearable antennas and introduces planar monopole antennas commonly used in the communication field as GIS PD detection sensors and carried out research on flexible planar monopole sensing technology built into GIS PD. The VSWR of monopole antenna in the UHF low band is optimized by the meandering technique. The size of the designed flexible antenna is 142 mm × 195 mm × 0.28 mm. The simulation and physical test results show that the improved monopole antenna with meandering technology has a VSWR of ≤2 in the frequency bands 570 MHz–830 MHz, 1.38 GHz–1.8 GHz, and 2.2 GHz–2.76 GHz when the bending radius is 0 mm, 200 mm, and 400 mm, respectively. The VSWR in the frequency band 450 MHz–3 GHz is ≤5. A 220 kV GIS PD detection platform was built to test the performance of the designed antenna, and the results showed that the antenna could detect the PD signal after bending deformation with a high Signal Noise Ratio (SNR).

A high-performance sensor for detecting SF6 decomposition components (H2S and SOF2) was fabricated via hydrothermal method using Au nanoparticles/tin oxide/reduced graphene oxide (AuNPs-SnO2-reduced graphene oxide [rGO]) hybrid nanomaterials. The sensor has gas-sensing properties that responded and recovered rapidly at a relatively low operating temperature. The structure and micromorphology of the prepared materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Raman spectroscopy, energy-dispersive spectroscopy (EDS), and Brunauer-Emmett-Teller (BET). The gas-sensing properties of AuNPs-SnO2-rGO hybrid materials were studied by exposure to target gases. Results showed that AuNPs-SnO2-rGO sensors had desirable response/recovery time. Compared with pure rGO (210/452 s, 396/748 s) and SnO2/rGO (308/448 s, 302/467 s), the response/recovery time ratios of AuNPs-SnO2-rGO sensors for 50 ppm H2S and 50 ppm SOF2 at 110°C were 26/35 s and 41/68 s, respectively. Furthermore, the two direction-resistance changes of the AuNPs-SnO2-rGO sensor when exposed to H2S and SOF2 gas made this sensor a suitable candidate for selective detection of SF6 decomposition components. The enhanced sensing performance can be attributed to the heterojunctions with the highly conductive graphene, SnO2 films and Au nanoparticles.

Content-centric networking (CCN) aims to improve network reliability, scalability, and security by changing the way that information is organized and retrieved in the current Internet. One critical issue in CCN is in-network cache allocation. It is known that in-network caching mechanisms are vulnerable to distributed denial of service attacks, especially to pollution attacks. That is, a caching mechanism under pollution attacks cannot work well. The past years witnessed kinds of proposals of cache allocation mechanisms. However, none of them could effectively allocate in-network cache while defending against attacks. In this paper, we propose a lightweight non-collaborative cache allocation approach (IFDD), which could not only enhance in-network caching performance in terms of the cache hit ratio and the request processing delay, but also defend against pollution attacks. By lightweight, we mean that IFDD generates low communication overhead (due to non-collaboration) and computational overhead at routers. The key idea behind IFDD is to combine the content popularity with the content locality in making caching decision. Extensive simulation results on ndnSIM platform demonstrate the capability of the proposed approach in improving cache allocation performance while reducing the impact of pollution attacks.